Explosive composition



LOSWE QOSITION Claude H. Carey, W A

Atlas Powder Comp corporation of Boise w Del, assignor to at Del. b

No Drawing. Application August 3, 1940, Serial No. 351,213

'17 Claims.

This invention relates to a new type of detonating explosive andimproved method of preparing the same comprising water soluble nitratesand a non-explosive, combustible, oily material. An object of thepresent invention is the production of a water soluble nitrate typeexplosive having suflicient sensitivity for use as a commercialexplosive withoutthe requirement that it be. primed with a cartridge ofdynamite or the like.

Another object of the invention is the produc-. tion of such anexplosive by the admixture of materials which are in themselvessubstantially incapable of detonation.

Other objects of the invention will hereinafter more fully appear.

It is known in' the explosive art that for ex- I plosives to beeffective in their use they must possess sufiicient sensitivity forsatisfactory propagation. Explosive compositions containing a highpercentage of ammonium nitrate have been heretofore disclosed, which arenot cap sensitive and, for this reason cannot be used in :bl-astingoperations as explosives without an auxiliary priming charge. Forexample, one proposal utilizes a cap sensitive central corein compressedcylinders of an explosive, wherein the nitrate and oily substances hasthe efiect of reduclng the sensitivity, I have'found that by in-.

corporating such oxygen consuming ingredients with the ammonium nitrateand non-explosive oily substance during the mixing and heating,explosives may be produced which will completely detonate in a 1%" x 8"paper cartridge when initiated by a No. 8 commercial blasting cap. Theincorporation of these oxygen consuming ingredients is advantageous inthat it permits the full development of the disruptive .7 crystals inintimate contact with thin films of oil,

or fat, are furnished with sufilcient oxidizable material inmicroscopical, or even molecular dimansions, to ofier an idealcombination for very large mass of the charge was insensitive andrequired the continuous cap sensitive core throughout the cylindricalcharge for a satisfactory detonation and propagation of the explosion.Another proposed explosive requires a powerful booster charge for thepurpose of propagating the explosion throughout the insensitivematerial. There have also'been proposed explosive compositions ofcolloidal starch and soluble nitrates which are more sensitive thansimple mechanical mixtures of the ingredients, but which require aprimer or initial detonating charge or a secondary sensitizing componentin order that they may be detonated with assurance.

It is well known in the explosive art that a simple mixture of grainedammonium nitrate and a non-explosive oily substance or a coating of anon-explosive oily substance applied as a coating to the grains ofammonium nitrate has too low'a degree of sensitivity to be of practicalvalue as an explosive, especially in smallsized cartridges. Now I havefound that mixtures of ammonium nitrate and non-explosive oilysubstances, when mixed and heated, in the presence of water to form aplastic mass which is conjections and undulations, which are sensitiveto rapid decomposition of the constituents when subjected to flame andshock, such as would rev suit from a blasting cap. Grained compositions,by means of agitation and drying, cause comparatively large crystals tobe formed without exposed angular surfaces and are coated with anexcessive amount of the oily substances which reduces the sensitivity ofthe particles todetonation. Fragmentation of the hard dried compositionsexposes the minute crystals and allows the maximum contact to thepropagating wave and flame by outcropping crystals at the surface of thefracture. Moreover, the dried fractured granules present surfaces fromthe interior which are highly irregular due to the fact that thegranules being case hardened before much of the moisture has beenrembved only permit shrinkage to take place in the interior of thehardened granule shell by the formation of voids which were occupied bythe concentrated solutions of the soluble salts. As a result of the moreporous structure of the interior of the granule than the surface, thefaces of the fractured particles ofier more minute prodetonation. Thisis particularly true when other combustible materials such as starch,cereal flours or gelatine are used. The increased sensiverted intostrings or vermicelli, and then dried or partially dried to a hardstate, followed by fragmentation so as to pass a 14 mesh or finer Tylerstandard screen, completely detonated (when substantially dry) in a 1%"x 8" paper cartridge by the initiation ofa #8 commercial blasting cap.Although the addition of oxygen consuming ingredients, such as finecarbonaceous materials, to my ultimate mixtures of ammonium tivlty andexplosive force of the explosive by the use of fuels result from theiroxidation by the available oxygen in the soluble nitrates.

The oily material employed in the explosive composition of the presentinvention may be a fatty oil such as cottonseed oil, sperm oil, castoroil, soya been oil, linseed oil, coconut oil and the like, or a fattyoil acid, such as lauric, myristic, palmitic, stearic, or oleic, fattyoil acid derivatives such as aluminum stearate, oleate, etc., or

tivity in obtoined when the a petroleum oil residue which isnon-volatile at from 20-50% free fatty acid, about 9.8% of which ispalmitic. Of the fatty oil acids suitable for use, I have found oleic tobe highly preferable, and petrolatum of the petroleum residues.

For the carbonaceous ingredients of the main fuel, I prefer a materialwhich has the ability to swell and readily absorb water such as cornstarch, tapioca flour, corn flour, gum arable, glue or gelatin, endmaterials rich in mannan such as vegetable ivory nut meal, carob beans,cofiee berries, and date seeds. l have found that substances such ascorn meal, starch. and glue, which contain smell amounts of ethersoluble oils or fats ere emcacious in promoting sensitivity.

In'addition to the main sensitized ingredient, or ammonium nitrate, Imay prefer to add other oxidants consisting of soluble nitrates such assodium nitrate and potassium nitrate, which will allow the strength orthe explosive to vary over a wider range, and meet specific requirementsin regard to density, velocity, and fume conditions.

in the preparation of the explosive compositions of the presentinvention, the water soluble nitrate, and the non-explosive,combustible, oily materiel (together with additional carbonaceousmaterial as a main fuel where it is desired to provide oxygen balance)are mixed with water,

and heated to a temperature in the neighborhood of 120 to 180 F. l havefound that the degree of temperature of mixing is not of greatimportance in securing desirable characteristics of the finishedproduct, but for ease in manufacture by securing an easily workableplastic mass,

the temperature may be varied according to the composition. In general Iprefer a temperature of from 120 to 140 F. although the invention is notto be considered limited in this respect as explosive compositions,having desirable sensitivities, may beobtained when mixing temperaturesas high as 180 F. are used.

Dining this heating and mixing, the composition becomes a soft,cohesive, plastic mass. Preferably this plastic mass is shredded byslicing with lmives, or by extruding it through orifices, so as toprovide (shredded) particles or vermicelli-like material having arelatively large surface area for subsequent conditioning. The particlesor vermicelli are rtially dried to a hard state, and thereafter groundor grained to the desired size, followed by complete drying. Theinvention is not to be considered as limited to this particular mannerof graining and coach tionlng the material, however, as other methodswill readily occur to those skilled in the art. Thus, for example, theplastic shredded mass me? be dried and ground to the desired porticlesize or it may be dried and crushed between rolls to the desiredparticlesiae.

The proportion or writer employed should be from b to oi the weight ofthe other mate ria s employed in the mixture. r 1- s. mush wateremployed n in the weight oi the the neighborhoml oi 11% or essence otheringredients. The water equivalent may be added in the-form of a solutionof nitrate of ammonia which serves equally as well as water alone.

The proportion of carbonaceous combustible material such as starch,cereal flour, tapioca flour, and vegetable ivory meal, may vary from 5to 25% depending on the final oxygen balance of the composite explosivemixture as used in the field.

The non-explosive, combustible, oily material is the sensitizing agentin the explosive composition, and should be present in small amountswithin definite limits if optimum sensitivity is to be obtained. Thus,where a petroleum oil residue such as petrolatum or a fatty oil acid isemployed in the composition as the sensitizing agent, it should bepresent in an amount not greater than 3.0% by weight on a dry basis, as

it has been found that greater proportions result in an insensitiveproduct. Combinations of 1.0% paramn and 0.5% oleic acid or 1.0% oleicacid and 0.3% paramn are excellent sensitizers.

In the preparation of the composition, the water soluble nitrate may bein any of the usual forms commonly employed in the explosive industry,or in the form of a water solution of the nitrate. The term coating ashereinafter used will refer to a mixture of 75% paraflln and 25%petrolatum, which is applied to grained ammonlum nitrate for the purposeof preventing moisture absorption in transportation and storage. Ifdesired the ammonium nitrate may be precoated with at least part of theoily sensitizer employed. Although water soluble inorganic nitretesother than ammonium nitrate, as for example, nitrate of soda, may beemployed along with ammonium nitrate, it has been found that thesensitivity of the explosive composition tends to decrease as theproportion of such other water soluble nitrates is increased. I havefound that in order to obtain the desired sensitivity in these explosivecompositions, their water soluble nitrate content should consist of atleast ammonium nitrate.

Where the composition is deficient in oxidizable matter and there is asubstantial excess of oxygen present in the composition, I may add tothe idants. The addition of such materials permits the proper adjustmentto be made for theoxygen balance so that ultimate mixture will exert itsfull disruptive force in the bore hole. By a. variation in the quantityof thevarlous materials as well as their degree of fineness it ispossible to vary the strength, density. and velocity of the explosive. i

In the following non-limiting examples of explosive compositions of thepresent invention, and of method of preparing the some, the partsreferred to are parts by weight. Where measured in inches, thesensitivities were determined by the space oi on air gap measured ininches between two out ends or an 1%," x 8" cartridge lying on thegrolmd and joined together by 2% wraps of 60 lb. new and the d atom-tingwave initiated by a #6 blasting cap in one of the halves .causedcomplete detonation of the two half cartridges.

At this stage the mixture becomes a soft, cohesive, plastic mass, whichis forced through a square mesh'screen having .084 in. openings, andwire of .041'in. diameter. The grains or vermicelli so produced are thenpartially dried by means of an air blast having a temperature from 80 to115 F., so that moisture content is reduced to about 1.6%. The hard,almost vitreous, grains are then fractured and broken by rubbing themover, and through, a wire screen having openings of .039 in., and a wirediameter of .032 in.. A final drying is carried out at a temperature of1307 F. to 0.44% moisture. The finished product when packed in 1%" x 8"parafiin sprayed paper shells gives an average cartridge count of about166 cartridges per 50#, and has a. sensitivity of 1" Example 1 Example 45 Ingredient g gs, 3 Ingredient 3 ag 53 Ammonium t w 7 oa PgftofloPgfglo 223? t r io r n edifitaaiiijiit: "32 15, 1.06 mmwmnmmmm Totalnitrate of ammonia and coatimz 8,700 87.00 The ammonium nitrate andwater are thor- Tap 740 660 M oughly mixed, and then the petrolatumadded, ggggggggdg ids 5 3 3 6,3 and the mixture thoroughly incorporatedin a aci so 50 0.50 steam jacketed dough mixer, and heated to 150 15 F.The amount of water present will be approxi- The dry ingredients of theabove composition mately 5.35% of the total mixture. The soft arethoroughly mixed in the dough mixer as in semi-plastic mass is forcedthroughasquare mesh Example 3 and brought up to a temperature of screen,having .096 in. openings, and .047 in. wire. 180 F. The plastic mass isconverted into vermi- The grains or vermicelli so produced are partiallycelli and air treated as in Example 3, and dried dried by means of anair blast having a temperaat 128 F. The dried material is fragmented ina ture from 80 to 100 F., so that the moisture mill so as to passaTylerstandard 14 mesh screen. content is reduced to a point where the grainsor The product packed in 1%" x 8" paper shells vermicelli will notcoalesce when submitted to sprayed with parafin, yields 148 cartridgesper 50 complete drying. The material is further treated 2 lbs., andconsistently detonates in the open with a at a temperature of 100 to 140F. for nearly #6 blasting cap. complete removal of the moisture. Thedried Example 5 mass is fragmented by means or a mill, or crushing rollsso as to pass a standard 40-mesb. screen. a Gross Dry Dry The fragmentedmaterial when packed mgtedent weight weight weight 1 x 8" parafinsprayed paper shells gives an average cartridge count of 169 cartridgesper 50 Grained ammonium nitrate 0.3% Parts Parts Percent hasasensiiivityof itfitiimenaieae' aiisiax:3:31;: it

Example 2 Total ammonium nitrate and coating 1,839 91.85 A compositionsimilar to that in Example 1, $33 1 33 {:53 with the exception thatoleic acid is substituted m for petrolatum in the same proportion. AfterThe ammonium nitrate and tapioca flour are prepanflg the composltion ina manner 0 mixed in a jacketed mixer and the solution and h fimshedProduct has equal Sensltmtypalm grease added, and the mixture heatedwith Example 3 mixing to 130 F. The plastic mass is converted intovermicelli and air treated as in Example 3. The grains or'verm'icelliare dried at 135 F., and ingredients ,g gf ag 3 3' passed throughcrushing rolls so as to pass a Tyler standard 20-mesh screen. Theexplosive Pam Pam composition so produced when packed in Nitrateoiammonla(0.3% coating).. 7,969 7,969 1%" x 8" parafiin sprayed papershells gave 169 Ammmmm mate 1 11983 236 cartridges per lbs. and had asensitivity of 9,205 9205 50 x p 6 $25 700 5.00 95 95 Ingredient 93$ gg' ag The amount of water present approximately (mined ammonium meme0.5% Pam m Pmm 12% of the total weight of the mixture. The amco t c)-.

------- 7,980 7, mon'ium nitrate and starch are intimately mixed Ammmmand warmed in a jacketed dough mixer, and the Total ammonium nitrate and9 m 92 22 liquids then introduced. By means of heat from "955' 1 theheating jacket, the temperature of the mass Wo 99 during the mixing isgradually raised to F.

The grained ammonium nitrate and flour are mixed in a jacketed mixer andthe oil and liquids added, followed by heating and mixing to F. Theplastic mass so produced is passed through a square mesh screen having.084 in. openings, and .041 in. diameter wire. This product is partiallydried and then grained through a square mesh screen, having .039 in.openings, and .032 in. diameter wire. The grains are finally dried at atemperature of 166 F. when packed in 1%" x 8" paraflin coatedshells'the'stick count was about 17'! per 50 lbs. and these cartridgesdetonated in the open with a #8 blasting cap.

Emmple 7 An explosive composition prepared as in Example 6, but havingraw linseed oil substituted tor the sperm oil. This explosivecomposition will also consistently detonate in the open with a. #8blasting cap; when packed 170 1%"x8" cartridges per 50 lbs.

Example 8 Gross D D Ingredient weight weight we t Groined ammoniumnitrate (0.3% Ports Pom Percent coatigf) 6, 000 6, 000 Ammo um nitratesolution l, 480 913 Total nitrate of ammonia 8,913 91. 89 1 Water 250Tapioca flour 590 510 6. 78 Aluminum steerste 100 100 l. 38

Emple 9 I I Gross Dry Dry M Weight Weight Weight Gruined nmmoniumnitrate (0.3% Pcflo Part Percent coating) a, son 6. soc Ammonium nitratesolution 1,900 l, 208 Water e00 'lotol ammonium nitrate and cost- 8, 0%80. 1G Tapioca flour 250 '210 2. 1% Corn menl M0 450 4. 60 Vegetableivory meal l, 230 l, 205 12. 03 Oleic acid 100 100 1.00

Gross D weight wag]:

Grnined ammonium nitrate (0.3%

The dry ingredients are mixed in a jacketed mixer, and then the liquidsadded and heated and mixed until a temperature of 180 F. is attained.The would contain opproximotely 11.1% water. The plastic mass soproduced is forced through an extruding machine so as to term equal-corround vermicelli, having on approxlmote crollaocflonnlomotmmllmimvlthpirtreatment for case hardening, followed by drying at a temperature from110 to 170 F. The dried vermicelli is fragmented by crushing or grindingin a mill to pass a -mesh Tyler standsrd screen. The fragmented materialwhen packed 15s 1%" x8" cartridges per lb. case gives s sensitivity of2". When packed 147 11%" xii" cartridges the sensitivity is about /2.

30* dough i removed and forced through a. screen as transferred to a dryhouse ond dried for 16 hours at 150 F. After removal from the dry houseit is cooled and iragmented by moons of metal rolls to pass a QO-meshstandard screen. A. sensitivity of 2" is obtained with s. #6 esp whenposited 43 g in 1%" x 8" paper cartridges yielding: 3163 per 50 lb.case.

It can be seen from the foregoing examples that each or the explosivecompositions was capable of being packed in 1% n 8" cortridges to 2.density within the rouge of from M5 to 1% 11%. x 8" cartridges per 50lb". case, at which den-- sity it was sensitive to detonzition with e.lilo. 0 commercial blasting cap.

The method of preparing the explosive compositions and mixtures of thepresent invention may be controlled to produce ultimate products ofvarious densities, sensitivities, end velocities. The compositionsprepared with higher mining temperstures such as 150 generally hove a.greater density than those prepored with lower mining temperatures inthe neighborhood oi F. It is desirable to hovethe combustible redientsin as iine a state of subdivision es practical in order to obtainhomogeneity.

in many types of blasting operations it is important to have theexplosive meet definite re quirements with respect to density andsensitivity. in other words, many blasting operations Y require highbuikstrensth. That such high density ammonium nitrate explosives arecharacterized by having a low sensitivity is well known in the art. Bycontrolling the particle size oi my ultimate mixture it is possible toregulate these characteristics of the explosive.

Also bymixing the fragmented explosive composition of the presentinvention with straizht ammonium nitrate, a density hlzher than one or acartridge count as low as 125 1% x 8" cartridges per 50 lbs. may beobtained and particulorly when relotively coarse straight ammoniumtridges.

assasea nitrate is employed as set forth in the following example. Thusone part of the explosive com position of Example (passing a 40 meshscreen) is mixed with one part of grained ammonium nitrate with 0.3%coating, said ammonium nitrate passing a 10-mesh screen and 95% beingheld on a 60-mesh screen. The resulting explosive has thefollowingapproximate analysis on the dry basis:

Percent Ammonium nitrate 89.7 Tapioca flour 3.5 Vegetable ivory meal 6.0Oleic acid 0.5

Coating 0.3

This mixture packed in 1%" x 8" paraihn sprayed paper shells givesa'cartridge count of about 129 cartridges per 50 lbs., and detonates inthe open with a #8 blasting cap. In this embodiment of the invention,the explosive comprising the fragmented product admixed with straightammonium nitrate is characterized by sensitivity to detonation with aNo. 8 blasting cap even though the straight ammonium nitrate is presentin proportions as high as 50% by weight of the explosive. i

Where referred to in this specification and appended claims, the termstraight ammonium nitrate" means ordinary commercial grade ammoniumnitrate such as conventionally grained ammonium nitrate containing'asmall amount of impurities and which generally is coated with a smallproportion of a moisture resisting material such as petrolatum,paraflin, etc.

By these various methods of preparation, a nonexplosive oily substance,soluble nitrates, and combustibles may be combined for compositions ofdesired sensitivity, with cartridge counts in the 1 x 8" size rangingfrom 125 to 185 and upward, cartridges per 50 lbs. Various combustibleswhich act as sensitizers and accelerators; as for example, aluminum andterm silicon powders may be added to the mixture.

In the foregoing examples and discussions of the explosive compositionsof the present invention, their embodiment in cartridge form has beenillustrated by reference to 1%" x 8" car- This small cartridge has beenchosen for purposes of illustration because the small diametercartridges are more dimcult to detonate than the larger sizes. This isparticularly true where a plurality of cartridges are laid end to end,and the detonation of an end cartridge by a blasting cap must bepropagated from one cartridge to another, to detonate the series. thisspecification, where it is stated that cartridges detonated with ablasting cap it is meant that one or more of a series of'cartridgesplaced end to end completely detonated unconfined, when detonated withthe blasting cap. It is obvious that the explosive composition of thepresent invention may be embodied in larger diameter cartridges,- whichinherently have a greater ability to propagate the detonating impulse.The explosive compositions are also excellently suited for use in loosegranular form to be charged directly into the bore hole.

In the foregoing examples, detonation of the explosive composition andmixtures were obtained in the open. Since propagation'of the detonatingimpulse is always more easily accomplished when the explosive is underconfinement of a bore hole, it will be readily apparent to those skilledin the art that the compositions and mixtures of the present inventionare of sumcient sensitivity to make them commercially useful without therequirement that they be primed.

The sensitivity of the explosive composition is believed to be due toits physical characteristics, and to a definite uniform physicalrelationship ofthe various particles to-each other. Since nolocalizedsupersensltivity can occur, the explosive offers a relatively highdegree of safety in its use.

' Furthermore, the handling and transportation of the raw materialsnecessary for .the production of the composition can be safely carriedout as the ingredients themselves are substantially incapable ofdetonation.

Having fully described the invention what I claim is as' follows:

.1. The process of preparing an explosive com-' position whichcomprisesintimately incorporating a. water-soluble nitrate consisting ofat least ding the plastic mass so produced into coarse,

firm particles, drying the particles to a hard state under conditionssuch that the particles will not coalesce, and fragmenting the hardparticles to pass a 14 mesh screen.

2. The process of preparing an explosive compositionwhich comprisesintimately incorporating a water-soluble nitrate consisting of at least.onium nitrate with a small sensitizing proportion-of a fatty oil acid,said incorporation being conducted in the presence of water and heattoi'orm a plastic mass, shredding the plastic mass so produced intocoarse, firm particles, drying the particles-to a hard state underconditions such that the particles will not coalesce, and fiasmentingthe hard particles to pass a 14 mesh screen.

3. The process of preparing an explosive composition whlch comprisesintimately incorporating a water-soluble nitrate consisting of at least60% ammonium nitrate with a. small sensitizing proportion of petrolatum,said incorporation being conducted in the presence of water and heat toform a plastic mass, shredding the plastic mass so produced into coarse,firm particles, drying the. particles to a hard state under conditionssuch that the particles will not coalesce,

and fragmenting the hard particles to pass a 14 mesh screen.

4. The process of preparing an explosive composition which comprisesintimately incorporatin; a water-soluble nitrate consisting of at least60% ammonium nitrate with not more than about 3% by weight or anon-explosive oily material, said incorporation being conducted in thepresence of water and heat to form a plastic mass. shredding the plasticmass so produced into coarse, firm particles, drying the particles underconditions such that the particles will not coalesce, finaldrying ofsaid particles being conducted at a temperature above F., andtragmenting said particles to pass a 14 mesh screen, said fraentingbeing conducted after the said particles have been dried at leastsuiiiciently so that they will not coalesce at a temperature of 100 F.

5. The process as set forth in claim 4 and wherein the incorporation iscarried out in the presence of 5% to 12% water and at a temperatureranging from to F.

6. The process of preparing an explosive composition which comprisesintimately incorporating a water-soluble nitrate consisting of. at least80% ammonium nitrate with oxidizable material present in an amount atleast suflicient to balance the oxygen content of the nitrate, saidmaterial including a small sensitizing proportion of non-explosive, oilymaterial, said incorporation being conducted in the presence or waterand, heat to form a plastic mass, shredding the plastic mass 50 producedinto coarse, firm particles, drying theparticles to a hard state underconditions such that the particles will not coalesce, and fragmentingthe hard particles to pass a 14 mesh screen.

7. The process of preparing an explosive composition which comprisesintimately incorporating a water-soluble nitrate consisting of at least60% ammonium nitrate with oxidizable material present in an amount atleast sumcient to balance the oxygen content of thenitrate, saidmaterial including a small sensitizing proportion of fatty oil acid,said incorporation being conducted in the presence of water and heat toform a plastic mass, shredding the plastic mass so produced into coarse,firm particles, drying the particles to a hard state under couditionssuch that the particles will not coalesce and fragmenting the hardparticles to pass a 14 mesh screen.

- 8. The process of preparing an explosive com position'which comprisesintimately incorporating a water-soluble nitrate consisting of at least60% ammonium nitrate with oxidizable material present in an amount atleast sufficient to balance the oxygen content'oi the nitrate, saidmaterial including a small sensitizing proportion 01 petrolatum, saidincorporation being conducted in the presence of water and heat to forma plastic mass, shredding the plastic mass so produced intd' coarse,firm particles, drying the particles to a hard state under conditionssuch that the particles will not coalesce and fragmenting the hardparticles to pass a 14 mesh screen.

9. An explosive composition comprising an explosive component consistingor discrete particles of an intimate mixture prepared in accordance withthe process of claim 1, said mixture being free of metal and explosivesensitizer ingredients,

, said explosive component, per se, being capable of being packed to adensity lower than that corresponding to 145 1%, x 8" cartridges per 50-pound case, at which density and diameter it is consistently sensitiveto detonation with a No. 8 cap.

10. An explosive composition comprising an explosive componentconsisting oi discrete particles of an intimate mixture prepared inaccordance with the process of claim 2, said mixture bein free of metaland explosive sensitizer ingredients, said explosive component, per se,being capable of being packed to a density lower than that correspondingto 145 1 x 8" cartridges per 50- pound case, at which density anddiameter it is consistently sensitive to detonation with a No. 8

cap.

l1. Anvexplosive composition comprising an ex- 4 plosive componentconsisting of discrete particles ofan intimate mixture prepared inaccordance with the process of claim 3, said mixture bein free of metaland explosive sensitizer ingredients, said explosive component, per se,being capable oi being packed to a density lower than that correspondingto 145 1% x 8" cartridges per 50- poundcase, at which density anddiameter'it is consistently sensitive to detonation with, a No. 8

cap.

12. An explosive composition comprising. an exacetates .said explosivecomponent, per se, being capable of being packed to a density lower thanthat corresponding to 1% x 8" cartridges per 50- pound case, at whichdensity and diameter it is consistently sensitive to detonation with aNo.

8 cap.

13. An explosive composition comprising an explosive componentconsisting of discrete particles of an intimate mixture preparedin'accordance with the'process of claim 6, said mixture being free ofmetal and explosive sensitizer ingredients, said explosive component,per se, being a capable of being packed'to a density lower than thatcorresponding to 145 1 /4)! 8" cartridgesper 50-pound case, at whichdensity and diameter it is consistently sensitive to detonation with aNo., 3 cap.

14. An explosive composition comprising an explosive componentconsisting of discrete particle's-of an intimate mixture prepared inaccordance with the process of claim '7, said mixture being free ofmetal and explosive sensitizer ingre dients, said explosive component,per se, being capable of being packed to a density lower than thatcorresponding to 145 1% x 8" cartridges per 50-pound case, at whichdensity and diameter it is consistently sensitive to detonation with aNo. 8 cap.

15. An explosive composition comprising an explosive componentconsisting of discrete particles of an intimate mixture prepared inaccordance with the process of claim 8, said mixture being free of metaland explosive sensitizer ingredients, said explosive component, per se,being capable 01' being packed to a density lower than thatcorresponding to 145 1% x 8" cartridges per 50-pound case, at whichdensity and diameter it is consistently sensitive to detonation with aNo. 8 cap.

16. An explosive composition comprising an explosive componentconsisting of discrete particles of an intimate mixture prepared inaccordance with the process of claim 6, said mixture being free 01 metaland explosive sensitizer ingredients, said explosive component, per se,being capable of being packed to a density lower than that correspondingto 145 1% x 8" cartridges per fail-pound case, at which density anddiameter it is consistently sensitive to detonation with a No. 8 capand, admixed with said explosive component, straight ammonium nitrate.

1'7. An explosive composition comprising an explosive componentconsisting of discrete particles of an intimate mixture prepared inaccordance with the process 01 claim 6 but wherein the particles arefragmented to pass a 40-mesh screen, said mixture being free of metaland explosive sensitizer ingredients, said explosive component, per se,being capable of being packed to a density lower than that correspondingto 145 1% x 8" cartridges per til-pound case, at which density explosivecomponent, straight ammonium nitrate J present in a proportion notgreater than 50% by weight or the explosive, said explosive having a adensity corresponding to from 125 to 1% x 8" cartridges per ISO-poundcase and being sensitive to detonation with a No. 8 cap.

- CLAUDE H. CAREY.

